In a networking environment it is often important for entities involved in networking tasks to be able to estimate how much bandwidth is or could be available for a particular use. For example, if insufficient bandwidth is available, then it may not make sense to start a task that would have to be performed inadequately or later aborted. Often the streaming transmission of audio and video information requires a certain quality of service in order to provide a satisfactory user experience, and if that quality of service is not available then the user experience will be lacking.
Recent years have seen an increase in the popularity of networking technologies, and hence an increase in techniques intended to determine available bandwidth. Unfortunately, many of these techniques make assumptions that are not borne out in reality, and thus yield inaccurate estimations of available bandwidth. For example, the packet gap method (PGM) works correctly only if the narrow and tight link along an Internet path are the same.
The following references are incorporated herein by reference in their entireties for all that they disclose without exclusion, including the content of cited references therein, and may be of aid to the reader in understanding certain rudimentary aspects of bandwidth measurement: K. Lai and M. Baker, “Measuring Link Bandwidths Using a Deterministic Model of Packet Delay”, ACM SIGCOMM, August 2000, and J. Strauss and D. Katabi and F. Kaashoek, “A Measurement Study of Available Bandwidth Estimation Tools”, ACM/USENIX IMC, October 2003.